Data Sheet
June 2001
DSP16410B Digital Signal Processor
260
Agere Systems—Proprietary
Use pursuant to Company instructions
Agere Systems Inc.
8 Signal Descriptions
(continued)
8.3 System and External Memory
Interface
(continued)
EACKN—DSP16410B Acknowledges External Bus
Request:
Negative-assertion output. The SEMI
acknowledges the request of an external device for
direct access to an asynchronous external memory by
asserting EACKN. See the description of the EREQN
pin above for details. The software can read the state
of the EACKN pin in the EACKN field (
ECON1
[5]—see
Table 60 on page 110
).
ESIZE—Size of External SEMI Bus:
Input. The exter-
nal data bus size input determines the size of the active
data bus. If ESIZE = 0, the external data bus is config-
ured as 16 bits and the SEMI uses ED[31:16] and
3-states ED[15:0]. If ESIZE = 1, the external data bus
is configured as 32 bits and the SEMI uses ED[31:0].
ERTYPE—EROM Type:
Input. The external ROM type
input determines the type of memory device in the
EROM component (selected by the EROMN enable). If
ERTYPE = 0, the EROM component is populated with
ROM or asynchronous SRAM, and the SEMI performs
asynchronous accesses to the EROM component. If
ERTYPE = 1, the EROM component is populated with
synchronous ZBTSRAM and the SEMI performs syn-
chronous accesses to the EROM component.
EXM—Boot Source:
Input. The external execution
memory input determines the active memory for pro-
gram execution after DSP16410B reset. If EXM = 0
when the RSTN pin makes a low-to-high transition,
both cores begin execution from their internal ROM
(IROM) memory at location 0x20000. If EXM = 1 when
the RSTN pin makes a low-to-high transition, both
cores begin execution from external ROM (EROM)
memory at location 0x80000. If the cores begin execu-
tion from external ROM, the SEMI arbitrates the
accesses from the two cores.
8.4 SIU0 Interface
SID0—External Serial Input Data:
Input. By default,
data is latched on the SID0 pin on a falling edge of the
input bit clock (SICK0) during a selected channel.
SOD0—External Serial Output Data:
Output. By
default, data is driven onto the SOD0 pin on a rising
edge of the output bit clock (SOCK0) during a selected
and unmasked channel. During inactive or masked
channel periods, SOD0 is 3-state.
SICK0—Input Bit Clock:
Input/output. SICK0 can be
an input (passive input clock) or an output (active input
clock). The SICK0 pin is the input data bit clock. By
default, data on SID0 is latched on a falling edge of this
clock, but the active level of this clock can be changed
by the ICKK field (
SCON10
[3]—
Table 111 on
page 188
). SICK0 can be configured via software as
an input (passive, externally generated) or an output
(active, internally generated) via the ICKA field
(
SCON10
[2]) and the ICKE field
(
SCON3
[6]—
Table 104 on page 185
).
SOCK0—Output Bit Clock:
Input/output. SOCK0 can
be an input (passive output clock) or an output (active
output clock). The SOCK0 pin is the output data bit
clock. By default, data on SOD0 is driven on a rising
edge of SOCK0 during active channel periods, but the
active level of this clock can be changed by the OCKK
field (
SCON10
[7]). SOCK0 can be configured via soft-
ware as an input (passive, externally generated) or an
output (active, internally generated) via the OCKA of
SCON10
[6]) and the OCKE field (
SCON3
[14]).
SIFS0—Input Frame Synchronization
: Input/output.
The SIFS0 signal indicates the beginning of a new
input frame. By default, SIFS0 is active-high, and a
low-to-high transition (rising edge) indicates the start of
a new frame. The active level and position of the input
frame sync relative to the first input data bit can be
changed via the IFSK field (
SCON10
[1]) and the IFS-
DLY[1:0] field (
SCON1
[9:8]—
Table 102 on page 183
),
respectively. SIFS0 can be configured via software as
an input (passive, externally generated) or an output
(active, internally generated) via the IFSA field
(
SCON10
[0]) and the IFSE field (
SCON3
[7]).
SOFS0—Output Frame Synchronization:
Input/out-
put. The SOFS0 signal indicates the beginning of a
new output frame. By default, SOFS0 is active-high,
and a low-to-high transition (rising edge) indicates the
start of a new frame. The active level and position of
the output frame sync relative to the first output data bit
can be changed via the OFSK field (
SCON10
[5]) and
the OFSDLY[1:0] field (
SCON2
[9:8]—
Table 103 on
page 184
), respectively. SOFS0 can be configured via
software as an input (passive, externally generated) or
an output (active, internally generated) via the OFSA
field (
SCON10
[4]) and the OFSE field (
SCON3
[15]).